A cast iron paperweight is in the shape of a half-sphere with a diameter of 8.2cm. The cast iron has a density of 7.3g/cm^3. What is the mass of the paperweight, in grams?

a. 16860

b. 8430

c. 1054

d. 2107

Answer: C

1054 g

Explanation:

Given that the object is in the shape of semi sphere with diameter of 8.2cm. And density of 7.3g/cm^3.

From definition of density,

Density = mass/volume

Volume of a half - sphere = 2/3πr^3

Volume = 2/3 * 3.143 * 4.1^3

Volume = 144.35 cm^3

Let make mass the subject of formula

Mass = Density * volume

Mass = 7.3 * 144.35

Mass = 1053.74g

The mass of the paperweight, in grams is 1054